In Classic ASP reading cXML Files, is it required to point your dtd link to local files? - asp-classic

Question

Unfortunately, we've inherited an old Classic ASP site and are writing new code for a round trip punch-out site. Reading in the cXML file, we're continually erroring out on the 2nd line !DOCTYPE cXML SYSTEM "http://xml.../cXML.dtd.
If we capture the location of the dtd file and change it to a local file, i.e., file:///c:/....dtd it works. Is there no way to get this to work using the http location? I'd rather not store all the dtd file versions locally.
Our Code is:
Dim olddtdvalue
Dim newdtdvalue
Dim xmlfilename
olddtdvalue = "http://xml.cxml.org/schemas/cXML/"
newdtdvalue = "file:///d:/Websites/FSIResponsive/cXML/"
xmlfilename ="PORS_" & formatdatetime(now,vblongdate) & " " & replace(formatdatetime(now,vblongtime),":","_") & ".xml"
set fs=Server.CreateObject("Scripting.FileSystemObject")
set f=fs.CreateTextFile("d:\WebSites\FSIResponsive\cXML\InFiles\" & xmlfilename,true)
f.write("remote host: " & request.ServerVariables("REMOTE_HOST") & vbcrlf & vbcrlf)
totalBytes = Request.TotalBytes
If totalBytes > 0 Then
xml = Request.BinaryRead( totalBytes )
for i = 1 to totalBytes
xmlstr = xmlstr + String(1,AscB(MidB(xml, i, 1)))
Next
f.write(xmlstr)
xml2 = xmlstr
xml2 = Replace(xml2,olddtdvalue,newdtdvalue)
End if
Set xdoc = Server.CreateObject("Microsoft.XMLDOM")
' Set xdoc = Server.CreateObject("MSXML2.DOMDocument.6.0")
xdoc.ValidateOnParse = True
xdoc.async = False
xdoc.resolveExternals = True
' response.write xml2
loadStatus = xdoc.loadXML(xml2)
As you can see, we've tried using MSXML2.DOMDocument.6.0, but that doesn't work either.
Thanks,
Alan
Update:
Here's the code I finally got working:
Dim xmlfilename
Dim URL
totalBytes = Request.TotalBytes
If totalBytes > 0 Then
xml = Request.BinaryRead( totalBytes )
for i = 1 to totalBytes
xmlstr = xmlstr + String(1,AscB(MidB(xml, i, 1)))
Next
xml2 = xmlstr
End if
Set xdoc = Server.CreateObject("MSXML2.DOMDocument.6.0")
xdoc.setProperty "ServerHTTPRequest", True
xdoc.setProperty "ProhibitDTD",False
xdoc.resolveExternals = True
xdoc.ValidateOnParse = True
xdoc.async = False
loadStatus = xdoc.LoadXML(xml2)
Alan